The present invention generally relates to semiconductor process tool monitoring systems, and more specifically relates to an integrated auditing system for monitoring one or more process tools used in connection with semiconductor fabrication.
Many different types of process tools are used in connection with semiconductor fabrication. Such process tools may include thermal processors, ion implantation systems, chemical vapor deposition reactors, optical steppers, reactive ion etchers, sputtering chambers, etc. Each process tool is driven by one or more sets of parameters, where the parameters define the operation of the process tool. Operating a process tool with the wrong settings, i.e., with the wrong parameters, can lead to product quality problems. Therefore, it is important to operate each process tool with the correct parameters within a semiconductor fabrication process. Tool setting parameters are for defining the tool operating condition (tool constants) and process conditions (tool recipe). Operating conditions determine how the tool works. For example, there are xe2x80x9cwafer handling robot positionxe2x80x9d, xe2x80x9cheater power ramp up ratexe2x80x9d. etc. Process conditions determine how the product is processed, for example, xe2x80x9cprocess timexe2x80x9d, xe2x80x9cpressure in process chamberxe2x80x9d, xe2x80x9cheater temperaturexe2x80x9d, etc.
Semiconductor fabrication has become more and more capable, but also more and more complicated. As such, the number of parameters used to define the operation of a given process tool has, in some cases, become very high. In some cases, as many as 6000 parameters or more are used to drive a process tool. As a result, when the parameters are incorrect, it is often very difficult, and at times impossible, to determine which parameters are, in fact, incorrect, so that the parameters can thereafter be corrected.
Several process tool suppliers have developed parameter verification systems in an attempt to address this problem. In such case, a verification system is provided by the process tool supplier, and a process tool user utilizes the verification system to check the parameters of the process tool. Typically, there are several different suppliers associated with a given set of process tools. Hence, a user is required to run a different verification system for each process tool type used. Because, each parameter verification system has a different operation style, it is challenging to check the parameters of each of the process tools. In most cases, parameter verification is performed manually. Considering the number of parameters, on certain tools this is a very time consuming task.
At least one software supplier has developed a system whereby a database of process tool parameters is maintained. The system is generally illustrated in FIG. 1 and provides that a tool user downloads the parameters from the system to the tool, and then operates the process tool using the parameters. This type of system requires a tool user to download one or more sets of parameters every time before a semiconductor device or material is processed by the process tool. As discussed above, the number of parameters for a given process tool may exceed 6000. Hence, data communication workload is a problem in implementing such a system.
A general object of an embodiment of the present invention is to provide an integrated process tool monitoring system for semiconductor fabrication. This system is an external system not integrated into the process tool.
Another object of an embodiment of the present invention is to provide a process tool parameter auditing system, where a process tool user need not run a different verification system for each process tool type used. A customized database allows each tool to have a unique parameter set.
Another object of an embodiment of the present invention is to provide a process tool parameter auditing system, where a process tool user need not download parameters every time before a semiconductor device or material is to be processed by the process tool.
Briefly, and in accordance with at least one of the foregoing objects, an embodiment of the present invention provides an integrated process tool monitoring system for semiconductor fabrication. Specifically, a process tool parameter auditing system, where a process tool user need not run a different verification system for each process tool type used and need not download parameters every time before a semiconductor device or material is to be processed by the process tool.